Polar bears live a feast and famine lifestyle. They are large animals (an adult males weighs 300-600kg) that live in the freezing tundra so they have huge metabolic needs. They normally prey on ringed seals but will eat almost anything they can catch, including walruses, birds, eggs and occasionally they supplement their diet with a big, juicy, beluga whale!

Beluga whales are distinctive for their pale skin and large melon shaped head. These animals can grow up to 5m (16ft) in length and live in large pods, mainly in the Arctic and Canadian Subarctic. Belugas live close to coastlines and in winter they occasionally become trapped in savsatts, small openings in ice packs. Belugas can find themselves the victims of shrinking savsatts, which they use to breath. Each animal will take a turn coming up for air and in the worst of winter, their movement is all that keeps the savsatt open.

Hence an opportunity that a wandering polar bear may chance by and certainly one he can’t resist. The bear will jump in the water, clubbing the trapped whale with his paw and gorging it with his claws. It may take several attempts but the bear usually succeeds in his catch and drags the whale’s carcass on to the ice for a feast. Other polar bears will share in the prize and any leftover kill will be happily devoured by scavenging arctic foxes and gulls.If you find this post interesting I encourage you to also check out Darren Naish’s very cool post on Wolf-Hunting Eagles!

I still don't believe it. Although polar bears are big and nasty I figure the beluga is bigger and whole lot heavier. How can the bear kill the whale and drag it out of the water? (I missed that part on the Blue Planet special.)

Why Fish Feet?

I study the evolution of terrestrial communities. My research begins in the Devonian, about 385 million years ago, when the first tetrapods (animals with four feet) evolved from fish. Fossils like Tiktaalik from Northern Canada blur the line between fish and amphibian because Tiktaalik has a mosaic of characteristics. There are many questions surrounding the evolution of tetrapods:

Why did vertebrates move on to land?

When did they begin to breath air?

Did their new limb structure develop in the water?

Our current understanding of the fossil record indicates that weight-bearing limbs developed while these animals were still living an aquatic lifestyle. I find this idea of fish with feet very funny and it makes me think of many new and important questions such as: